U.S. patent application number 13/521266 was filed with the patent office on 2012-12-06 for materials for organic electroluminescent devices.
This patent application is currently assigned to Merck Patent GmbH. Invention is credited to Herwig Buchholz, Irina Martynova, Teresa Mujica-Fernaud, Junyou Pan.
Application Number | 20120305851 13/521266 |
Document ID | / |
Family ID | 43495110 |
Filed Date | 2012-12-06 |
United States Patent
Application |
20120305851 |
Kind Code |
A1 |
Pan; Junyou ; et
al. |
December 6, 2012 |
Materials for Organic Electroluminescent Devices
Abstract
The present invention relates to compounds of the formula (1)
which are suitable for use in electronic devices, in particular
organic electroluminescent devices, and to electronic devices which
contain these compounds.
Inventors: |
Pan; Junyou; (Frankfurt Am
Main, DE) ; Buchholz; Herwig; (Frankfurt Am Main,
DE) ; Mujica-Fernaud; Teresa; (Darmstadt, DE)
; Martynova; Irina; (Griesheim, DE) |
Assignee: |
Merck Patent GmbH
Darmstadt
DE
|
Family ID: |
43495110 |
Appl. No.: |
13/521266 |
Filed: |
December 17, 2010 |
PCT Filed: |
December 17, 2010 |
PCT NO: |
PCT/EP2010/007744 |
371 Date: |
August 23, 2012 |
Current U.S.
Class: |
252/500 ;
528/423; 544/212; 544/229; 544/296 |
Current CPC
Class: |
C09B 69/109 20130101;
H01L 51/5096 20130101; C07D 251/22 20130101; C09B 11/04 20130101;
C09B 57/10 20130101; H01L 51/0061 20130101; C09B 57/00 20130101;
H01L 51/42 20130101; Y02E 10/549 20130101; H01L 51/0059 20130101;
C09B 57/007 20130101; H01L 51/0508 20130101; H01L 51/5012 20130101;
C07D 209/86 20130101; C09B 57/008 20130101; H01L 51/5048
20130101 |
Class at
Publication: |
252/500 ;
544/212; 544/296; 544/229; 528/423 |
International
Class: |
C07D 403/12 20060101
C07D403/12; H01B 1/12 20060101 H01B001/12; C07F 7/10 20060101
C07F007/10; C08G 73/06 20060101 C08G073/06; C07D 403/14 20060101
C07D403/14; C07D 409/14 20060101 C07D409/14 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 16, 2010 |
DE |
10 2010 004 803.8 |
Claims
1-15. (canceled)
16. A compound of the formula (1), ##STR00210## where the following
applies to the symbols and indices used: Ar.sup.1 and Ar.sup.2 is
on each occurrence, identically or differently, an aromatic or
heteroaromatic ring system having 5 to 60 aromatic ring atoms,
which is optionally substituted by one or more radicals R; Ar.sup.1
and Ar.sup.2 here may also be connected to one another by a single
bond and thus form a carbazole; Ar.sup.3 and Ar.sup.4 is on each
occurrence, identically or differently, a divalent aromatic or
heteroaromatic ring system having 5 to 30 aromatic ring atoms,
which is optionally substituted by one or more radicals R, with the
proviso that Ar.sup.3 and Ar.sup.4 do not contain any aryl groups
having more than two aromatic six-membered rings condensed directly
onto one another; Ar.sup.5 and Ar.sup.6 stands, identically or
differently on each occurrence, for a group of the following
formula (2), where the dashed bond indicates the position of the
link to N; ##STR00211## X is on each occurrence, identically or
differently, CR or N, with the proviso that at least two groups X
in Ar.sup.5 stand for N, and with the proviso that in each case a
maximum of three symbols X in the group of the formula (2) stand
for N; and furthermore with the proviso that, if the formula (2)
stands for a triazine, the radicals R are not equal to an alkoxy
group, a thioalkoxy group, chlorine or a substituted or
unsubstituted amino group; L is a divalent straight-chain alkylene,
alkylidene, alkyleneoxy or thioalkyleneoxy group having 1 to 40 C
atoms or a branched or cyclic alkylene, alkylidene, alkyleneoxy or
thioalkyleneoxy group having 3 to 40 C atoms, which is optionally
substituted in each case by one or more radicals R, where one or
more CH.sub.2 groups, is optionally replaced by Si(R).sub.2,
Ge(R).sub.2, Sn(R).sub.2, C.dbd.O, C.dbd.S, C.dbd.Se, C.dbd.NR,
P(.dbd.O)R, S.dbd.O, SO.sub.2, --O--, --S-- or --CONR-- and where
one or more H atoms is optionally replaced by D, F, Cl, Br, I, CN
or NO.sub.2, or a divalent aromatic or heteroaromatic ring system
having 5 to 30 aromatic ring atoms, which is optionally substituted
by one or more radicals R, where L does not contain any aryl groups
having more than two aromatic six-membered rings condensed directly
onto one another, or L is Si(R).sub.2, Ge(R).sub.2, O, S,
C(.dbd.O), S(.dbd.O), SO.sub.2, SF.sub.4, PR, P(.dbd.O)(R),
PF.sub.3, P(.dbd.S)(R), AsR, As(.dbd.O)(R), As(.dbd.S)(R), Sb,
Sb(.dbd.O)(R), Sb(.dbd.S)(R), N(Ar) or L is a combination of two,
three, four or five of these systems; R is on each occurrence,
identically or differently, a H, D, F, Cl, Br, I, CN, NO.sub.2,
N(Ar).sub.2, N(R.sup.1).sub.2, C(.dbd.O)Ar, C(.dbd.O)R.sup.1,
P(.dbd.O)(Ar).sub.2, B(R.sup.1).sub.2, B(OR.sup.1).sub.2,
Si(R.sup.1).sub.3, a straight-chain alkyl, alkoxy or thioalkyl
group having 1 to 40 C atoms or a branched or cyclic alkyl, alkoxy
or thioalkyl group having 3 to 40 C atoms or an alkenyl or alkynyl
group having 2 to 40 C atoms, each of which is optionally
substituted by one or more radicals R.sup.1, where one or more
non-adjacent CH.sub.2 groups is optionally replaced by
R.sup.1C.dbd.CR.sup.1, C.ident.C, Si(R.sup.1).sub.2,
Ge(R.sup.1).sub.2, Sn(R.sup.1).sub.2, C.dbd.O, C.dbd.S, C.dbd.Se,
C.dbd.NR.sup.1, P(.dbd.O)(R.sup.1), SO, SO.sub.2, NR.sup.1, O, S or
CONR.sup.1 and where one or more H atoms is optionally replaced by
D, F, Cl, Br, I, CN or NO.sub.2, an aromatic or heteroaromatic ring
system having 5 to 60 aromatic ring atoms, which may in each case
be substituted by one or more radicals R.sup.1, an aryloxy or
heteroaryloxy group having 5 to 60 aromatic ring atoms, which is
optionally substituted by one or more radicals R.sup.1, or an
aralkyl or heteroaralkyl group having 5 to 60 aromatic ring atoms,
which may in each case be substituted by one or more radicals
R.sup.1, where two or more adjacent substituents R may optionally
form a mono- or polycyclic, aliphatic, aromatic or heteroaromatic
ring system, which is optionally substituted by one or more
radicals R.sup.1; R.sup.1 is on each occurrence, identically or
differently, a H, D, F, Cl, Br, I, CN, NO.sub.2, N(Ar).sub.2,
N(R.sup.2).sub.2, C(.dbd.O)Ar, C(.dbd.O)R.sup.2,
P(.dbd.O)(Ar).sub.2, B(R.sup.2).sub.2, B(OR.sup.2).sub.2,
Si(R.sup.2).sub.3, a straight-chain alkyl, alkoxy or thioalkyl
group having 1 to 40 C atoms or a branched or cyclic alkyl, alkoxy
or thioalkyl group having 3 to 40 C atoms or an alkenyl or alkynyl
group having 2 to 40 C atoms, each of which is optionally
substituted by one or more radicals R.sup.2, where one or more
non-adjacent CH.sub.2 groups is optionally replaced by
R.sup.2C.dbd.CR.sup.2, C.ident.C, Si(R.sup.2).sub.2,
Ge(R.sup.2).sub.2, Sn(R.sup.2).sub.2, C.dbd.O, C.dbd.S, C.dbd.Se,
C.dbd.NR.sup.2, P(.dbd.O)(R.sup.2), SO, SO.sub.2, NR.sup.2, O, S or
CONR.sup.2 and where one or more H atoms is optionally replaced by
D, F, Cl, Br, I, CN or NO.sub.2, an aromatic or heteroaromatic ring
system having 5 to 60 aromatic ring atoms, which may in each case
be substituted by one or more radicals R.sup.2, an aryloxy or
heteroaryloxy group having 5 to 60 aromatic ring atoms, which is
optionally substituted by one or more radicals R.sup.2, or an
aralkyl or heteroaralkyl group having 5 to 60 aromatic ring atoms,
which is optionally substituted by one or more radicals R.sup.2,
where two or more adjacent substituents R.sup.1 may optionally form
a mono- or polycyclic, aliphatic, aromatic or heteroaromatic ring
system, which is optionally substituted by one or more radicals
R.sup.2; Ar is on each occurrence, identically or differently, an
aromatic or heteroaromatic ring system having 5-30 aromatic ring
atoms, which is optionally substituted by one or more non-aromatic
radicals R.sup.2; two radicals Ar which are bonded to the same N
atom or P atom may also be bridged to one another by a single bond
or a bridge selected from N(R.sup.2), C(R.sup.2).sub.2, O or S;
R.sup.2 is a H, D, F, CN, an aliphatic hydrocarbon radical having 1
to 20 C atoms, an aromatic or heteroaromatic ring system having 5
to 30 aromatic ring atoms, in which one or more H atoms is
optionally replaced by D, F, Cl, Br, I or CN, where two or more
adjacent substituents R.sup.2 may form a mono- or polycyclic,
aliphatic, aromatic or heteroaromatic ring system with one another;
m and n are on each occurrence, identically or differently, 0 or 1,
where m=n=1 if L stands for O, S or N(Ar).
17. The compound according to claim 16, wherein L is a divalent
straight-chain alkylene, alkylidene, alkyleneoxy or thioalkyleneoxy
group having 1 to 40 C atoms or a branched or cyclic alkylene,
alkylidene, alkyleneoxy or thioalkyleneoxy group having 3 to 40 C
atoms, which is optionally substituted in each case by one or more
radicals R, where one or more CH.sub.2 groups, which are not
adjacent, is optionally replaced by Si(R).sub.2, Ge(R).sub.2,
Sn(R).sub.2, C.dbd.O, C.dbd.S, C.dbd.Se, C.dbd.NR, P(.dbd.O)R,
S.dbd.O, SO.sub.2, --O--, --S-- or --CONR-- and where one or more H
atoms is optionally replaced by D, F, Cl, Br, I, CN or NO.sub.2, or
a divalent aromatic or heteroaromatic ring system having 5 to 30
aromatic ring atoms, which is optionally substituted by one or more
radicals R, where L does not contain any aryl groups having more
than two aromatic six-membered rings condensed directly onto one
another, or L is Si(R).sub.2, Ge(R).sub.2, O, S, C(.dbd.O),
S(.dbd.O), SO.sub.2, SF.sub.4, PR, P(.dbd.O)(R), PF.sub.3,
P(.dbd.S)(R), AsR, As(.dbd.O)(R), As(.dbd.S)(R), Sb, Sb(.dbd.O)(R),
Sb(.dbd.S)(R), N(Ar) or L is a combination of two, three, four or
five of these systems;
18. The compound according to claim 16, wherein at least one group
X, in the formula (2) which stands for Ar.sup.6 stand for N, and
the remaining groups X stand for CR.
19. The compound according to claim 16, wherein two or three groups
X, in the formula (2) which stands for Ar.sup.6 stand for N, and
the remaining groups X stand for CR.
20. The compound according to claim 16, wherein the group of the
formula (2) which stands for Ar.sup.5 is selected, identically or
differently on each occurrence, from the groups of the formulae (3)
to (11), ##STR00212## and in that the group Ar.sup.6 is selected
from the groups of the formulae (3) to (11) or from the groups of
the formulae (12) to (15), ##STR00213## where symbols used have the
meanings given in claim 16; the dashed bond here indicates the
position of the bond from the group to the nitrogen.
21. The compound according to claim 16, wherein the unit
--NAr.sup.5Ar.sup.6 is selected from the groups of the formulae
(16) to (27): ##STR00214## ##STR00215## ##STR00216## where symbols
used have the meanings given in claim 16, and the dashed bond
indicates the bond from this group to L or Ar.sup.4.
22. The compound according to claim 16, wherein Ar.sup.1 and
Ar.sup.2 stand, identically or differently on each occurrence, for
an aromatic or heteroaromatic ring system having 5 to 30 aromatic
ring atoms, which may in each case also be substituted by one or
more radicals R.
23. The compound according to claim 16, wherein Ar.sup.1 and
Ar.sup.2 stand, identically or differently on each occurrence, for
an aromatic or heteroaromatic ring system having 5 to 24 aromatic
ring atoms, which may in each case also be substituted by one or
more radicals R.
24. The compound according to claim 16, wherein the groups Ar.sup.1
and Ar.sup.2 are selected, identically or differently on each
occurrence, from the formulae (28) to (42), ##STR00217##
##STR00218## ##STR00219## where symbols used have the meanings
given in claim 16, and the dashed bond indicates the bond from this
group to the nitrogen.
25. The compound according to claim 16, wherein, if n=0 and/or m=0,
L is a divalent straight-chain alkylene or alkylidene group having
1 to 10 C atoms or a branched or cyclic alkylene or alkylidene
group having 3 to 10 C atoms, which is optionally substituted by in
each case one or more radicals R, where one or more CH.sub.2 groups
which are not bonded directly to N and are not adjacent is
optionally replaced by Si(R).sub.2, C.dbd.O, P(.dbd.O)R, S.dbd.O,
SO.sub.2, --O--, --S-- or --CONR-- and where one or more H atoms is
optionally replaced by D or F, or a divalent aromatic or
heteroaromatic ring system having 5 to 24 aromatic ring atoms,
which may also be substituted by one or more radicals R, or
Si(R).sub.2, C(.dbd.O), S(.dbd.O), SO.sub.2, P(.dbd.O)R or a
combination of two or three of these systems; and in that, if
m=n=1, L is selected from the above-mentioned embodiments or from
O, S or N(Ar).
26. The compound according to claim 16, wherein, if n=0 and/or m=0,
L is a divalent straight-chain alkylene or alkylidene group having
1 to 5 C atoms, or a branched or cyclic alkylene or alkylidene
group having 3 to 6 C atoms, which is optionally substituted by in
each case one or more radicals R, where one or more CH.sub.2 groups
which are not bonded directly to N and are not adjacent is
optionally replaced by Si(R).sub.2, C.dbd.O, P(.dbd.O)R, S.dbd.O,
SO.sub.2, --O--, --S-- or --CONR-- and where one or more H atoms is
optionally replaced by D or F, or a divalent aromatic or
heteroaromatic ring system having 5 to 24 aromatic ring atoms,
which may also be substituted by one or more radicals R, or
Si(R).sub.2, C(.dbd.O), S(.dbd.O), SO.sub.2, P(.dbd.O)R or a
combination of two or three of these systems; and in that, if
m=n=1, L is selected from the above-mentioned embodiments or from
O, S or N(Ar).
27. The compound according to claim 16, wherein m and n=1, and the
bridging unit L has a structure of the formula (145):
--(CR.sub.2).sub.p--(Y).sub.q-- formula (145) where R has the
meaning given in claim 16, and furthermore: Y is, identically or
differently on each occurrence, CR.sub.2, SiR.sub.2, GeR.sub.2, S,
O or NR; p is a number from 0 to 14; q is 0, 1, 2, 3 or 4;
p+q>0; with the proviso that a plurality of heteroatoms are not
bonded directly to one another.
28. The compound according to claim 27, wherein p is 0, 1, 2, 3, 4,
5 or 6; q is 0, 1 or 2.
29. A process for the preparation of a compound according to claim
16, comprising the reaction steps: a) synthesising a compound
G-(Ar.sup.3).sub.n-L-(Ar.sup.4).sub.m--NAr.sup.5Ar.sup.6 by
reaction of a compound
G-(Ar.sup.3).sub.n-L-(Ar.sup.4).sub.m--NH.sub.2 with a compound
G-Ar.sup.5 and G-Ar.sup.6, optionally with addition of a base
and/or a catalyst, where G stands for a reactive leaving group, in
particular fluorine, chlorine, bromine or iodine; and b)
introducing the group Ar.sup.1Ar.sup.2N-- by coupling a group
Ar.sup.1Ar.sup.2NH to Ar.sup.3 or L or by coupling a group
Ar.sup.1Ar.sup.2--N--Ar.sup.3-G to L.
30. An oligomer, polymer or dendrimer comprising one or more
compounds according to claim 16, where one or more bonds are
present from the compound according to the invention to the
polymer, oligomer or dendrimer.
31. An electronic device comprising the compound according to claim
16.
32. The electronic device according to claim 31, selected from the
group consisting of organic electroluminescent device (organic
light-emitting diode, OLED), organic integrated circuit (O-IC),
organic field-effect transistor (O-FET), organic thin-film
transistor (O-TFT), organic light-emitting transistor (O-LET),
organic solar cell (O-SC), organic dye-sensitised solar cell
(ODSSC), organic optical detector, organic photoreceptor, organic
field-quench device (O-FQD), light-emitting electrochemical cell
(LEC), organic laser diode (O-laser) and organic plasmon emitting
device.
33. An organic electroluminescent device comprising the compound
according to claim 16 is used as a matrix material for fluorescent
or phosphorescent emitters and/or in a hole-blocking layer and/or
in an electron-transport layer and/or in an electron-blocking or
exciton-blocking layer and/or in a hole-transport layer.
34. A formulation comprising at least one compound according to
claim 16 and at least one solvent.
35. A solution, dispersion or mini emulsion comprising at least one
compound according to claim 16 and at least one solvent.
36. A mixture comprising at least one compound according to claim
16 and at least one further compound.
Description
[0001] The present invention relates to materials for use in
electronic devices, in particular in organic electroluminescent
devices, and to electronic devices containing these materials.
[0002] The structure of organic electroluminescent devices (OLEDs)
in which organic semiconductors are employed as functional
materials is described, for example, in U.S. Pat. No. 4,539,507,
U.S. Pat. No. 5,151,629, EP 0676461 and WO 98/27136. The emitting
materials employed here are increasingly organometallic complexes
which exhibit phosphorescence instead of fluorescence (M. A. Baldo
et al., Appl. Phys. Lett. 1999, 75, 4-6). For quantum-mechanical
reasons, an up to four-fold energy and power efficiency is possible
using organometallic compounds as phosphorescence emitters. In
general, however, there is still a need for improvement in OLEDs,
in particular also in OLEDs which exhibit triplet emission
(phosphorescence), for example with respect to efficiency,
operating voltage and in particular lifetime. This applies, in
particular, to OLEDs which emit in the relatively short-wave range,
for example green.
[0003] The properties of phosphorescent OLEDs are determined not
only by the triplet emitters employed. In particular, the other
materials used, such as matrix materials, hole-blocking materials,
electron-transport materials, hole-transport materials and
electron- or exciton-blocking materials, are also of particular
importance here. Improvements in these materials can thus also
result in significant improvements in the OLED properties. There is
also still a need for improvement in these materials for
fluorescent OLEDs.
[0004] In accordance with the prior art, ketones (for example in
accordance with WO 2004/093207 or in accordance with the
unpublished application DE 102008033943.1) or phosphine oxides (for
example in accordance with WO 05/003253), inter alia, are used as
matrix materials for phosphorescent emitters. Furthermore, triazine
derivatives are used as matrix materials for phosphorescent
emitters (for example in accordance with WO 2007/063754 or WO
2008/056746). However, there is still a need for improvement, in
particular with respect to the efficiency and lifetime of the
device, on use of these matrix materials as in the case of other
matrix materials.
[0005] The object of the present invention is the provision of
compounds which are suitable for use in a fluorescent or
phosphorescent OLED, in particular a phosphorescent OLED, for
example as matrix material or as hole-transport/electron-blocking
material or exciton-blocking material or as electron-transport or
hole-blocking material. In particular, it is the object of the
present invention to provide matrix materials which are also
suitable for green- and blue-phosphorescent OLEDs. The object of
the present invention is furthermore to provide matrix materials
for phosphorescent emitters which have a small separation between
the S.sub.1 level and the T.sub.1 level, since compounds of this
type are particularly suitable for use as triplet matrix
material.
[0006] Surprisingly, it has been found that certain compounds
described in greater detail below achieve this object and result in
significant improvements in the organic electroluminescent device,
in particular with respect to the lifetime, the efficiency and the
operating voltage. This applies to red-, green- and
blue-phosphorescent electroluminescent devices, in particular on
use of the compounds according to the invention as matrix material.
The present invention therefore relates to these materials and to
organic electroluminescent devices which contain compounds of this
type.
[0007] The present invention therefore relates to a compound of the
following formula (1),
##STR00001##
where the following applies to the symbols and indices used: [0008]
Ar.sup.1, Ar.sup.2 is on each occurrence, identically or
differently, an aromatic or heteroaromatic ring system having 5 to
60 aromatic ring atoms, which may be substituted by one or more
radicals R; Ar.sup.1 and Ar.sup.2 here may also be connected to one
another by a single bond and thus form a carbazole; [0009]
Ar.sup.3, Ar.sup.4 is on each occurrence, identically or
differently, a divalent aromatic or heteroaromatic ring system
having 5 to 30 aromatic ring atoms, which may be substituted by one
or more radicals R, with the proviso that Ar.sup.3 and Ar.sup.4 do
not contain any aryl groups having more than two aromatic
six-membered rings condensed directly onto one another; [0010]
Ar.sup.5, Ar.sup.6 stands, identically or differently on each
occurrence, for a group of the following formula (2), where the
dashed bond indicates the position of the link to N;
[0010] ##STR00002## [0011] X is on each occurrence, identically or
differently, CR or N, with the proviso that at least two groups X
in Ar.sup.5 stand for N, and with the proviso that in each case a
maximum of three symbols X in the group of the formula (2) stand
for N; and furthermore with the proviso that, if the formula (2)
stands for a triazine, the radicals R are not equal to an alkoxy
group, a thioalkoxy group, chlorine or a substituted or
unsubstituted amino group; [0012] L is a divalent straight-chain
alkylene, alkylidene, alkyleneoxy or thioalkyleneoxy group having 1
to 40 C atoms or a branched or cyclic alkylene, alkylidene,
alkyleneoxy or thioalkyleneoxy group having 3 to 40 C atoms, which
may be substituted by in each case one or more radicals R, where
one or more CH.sub.2 groups, which are preferably not adjacent, may
be replaced by Si(R).sub.2, Ge(R).sub.2, Sn(R).sub.2, C.dbd.O,
C.dbd.S, C.dbd.Se, C.dbd.NR, P(.dbd.O)R, S.dbd.O, SO.sub.2, --O--,
--S-- or --CONR-- and where one or more H atoms may be replaced by
D, F, Cl, Br, I, CN or NO.sub.2, or a divalent aromatic or
heteroaromatic ring system having 5 to 30 aromatic ring atoms,
which may be substituted by one or more radicals R, where L does
not contain any aryl groups having more than two aromatic
six-membered rings condensed directly onto one another, or L is
Si(R).sub.2, Ge(R).sub.2, O, S, C(.dbd.O), S(.dbd.O), SO.sub.2,
SF.sub.4, PR, P(.dbd.O)(R), PF.sub.3, P(.dbd.S)(R), AsR,
As(.dbd.O)(R), As(.dbd.S)(R), Sb, Sb(.dbd.O)(R), Sb(.dbd.S)(R),
N(Ar), or L is a combination of two, three, four or five of the
above-mentioned systems; [0013] R is selected on each occurrence,
identically or differently, from the group consisting of H, D, F,
Cl, Br, I, CN, NO.sub.2, N(Ar).sub.2, N(R.sup.1).sub.2,
C(.dbd.O)Ar, C(.dbd.O)R.sup.1, P(.dbd.O)(Ar).sub.2,
B(R.sup.1).sub.2, B(OR.sup.1).sub.2, Si(R.sup.1).sub.3, a
straight-chain alkyl, alkoxy or thioalkyl group having 1 to 40 C
atoms or a branched or cyclic alkyl, alkoxy or thioalkyl group
having 3 to 40 C atoms or an alkenyl or alkynyl group having 2 to
40 C atoms, each of which may be substituted by one or more
radicals R.sup.1, where one or more non-adjacent CH.sub.2 groups
may be replaced by R.sup.1C.dbd.CR.sup.1, C.ident.C,
Si(R.sup.1).sub.2, Ge(R.sup.1).sub.2, Sn(R.sup.1).sub.2, C.dbd.O,
C.dbd.S, C.dbd.Se, C.dbd.NR.sup.1, P(.dbd.O)(R.sup.1), SO,
SO.sub.2, NR.sup.1, O, S or CONR.sup.1 and where one or more H
atoms may be replaced by D, F, Cl, Br, I, CN or NO.sub.2, an
aromatic or heteroaromatic ring system having 5 to 60 aromatic ring
atoms, which may in each case be substituted by one or more
radicals R.sup.1, an aryloxy or heteroaryloxy group having 5 to 60
aromatic ring atoms, which may be substituted by one or more
radicals R.sup.1, or an aralkyl or heteroaralkyl group having 5 to
60 aromatic ring atoms, which may in each case be substituted by
one or more radicals R.sup.1, where two or more adjacent
substituents R may optionally form a mono- or polycyclic,
aliphatic, aromatic or heteroaromatic ring system, which may be
substituted by one or more radicals R.sup.1; [0014] R.sup.1 is
selected on each occurrence, identically or differently, from the
group consisting of H, D, F, Cl, Br, I, CN, NO.sub.2, N(Ar).sub.2,
N(R.sup.2).sub.2, C(.dbd.O)Ar, C(.dbd.O)R.sup.2,
P(.dbd.O)(Ar).sub.2, B(R.sup.2).sub.2, B(OR.sup.2).sub.2,
Si(R.sup.2).sub.3, a straight-chain alkyl, alkoxy or thioalkyl
group having 1 to 40 C atoms or a branched or cyclic alkyl, alkoxy
or thioalkyl group having 3 to 40 C atoms or an alkenyl or alkynyl
group having 2 to 40 C atoms, each of which may be substituted by
one or more radicals R.sup.2, where one or more non-adjacent
CH.sub.2 groups may be replaced by R.sup.2C.dbd.CR.sup.2,
C.ident.C, Si(R.sup.2).sub.2, Ge(R.sup.2).sub.2, Sn(R.sup.2).sub.2,
C.dbd.O, C.dbd.S, C.dbd.Se, C.dbd.NR.sup.2, P(.dbd.O)(R.sup.2), SO,
SO.sub.2, NR.sup.2, O, S or CONR.sup.2 and where one or more H
atoms may be replaced by D, F, Cl, Br, I, CN or NO.sub.2, an
aromatic or heteroaromatic ring system having 5 to 60 aromatic ring
atoms, which may in each case be substituted by one or more
radicals R.sup.2, an aryloxy or heteroaryloxy group having 5 to 60
aromatic ring atoms, which may be substituted by one or more
radicals R.sup.2, or an aralkyl or heteroaralkyl group having 5 to
60 aromatic ring atoms, which may be substituted by one or more
radicals R.sup.2, where two or more adjacent substituents R.sup.1
may optionally form a mono- or polycyclic, aliphatic, aromatic or
heteroaromatic ring system, which may be substituted by one or more
radicals R.sup.2; [0015] Ar is on each occurrence, identically or
differently, an aromatic or heteroaromatic ring system having 5-30
aromatic ring atoms, which may be substituted by one or more
non-aromatic radicals R.sup.2; two radicals Ar which are bonded to
the same N atom or P atom may also be bridged to one another by a
single bond or a bridge selected from N(R.sup.2), C(R.sup.2).sub.2,
O or S; [0016] R.sup.2 is selected from the group consisting of H,
D, F, CN, an aliphatic hydrocarbon radical having 1 to 20 C atoms,
an aromatic or heteroaromatic ring system having 5 to 30 aromatic
ring atoms, in which one or more H atoms may be replaced by D, F,
Cl, Br, I or CN, where two or more adjacent substituents R.sup.2
may form a mono- or polycyclic, aliphatic, aromatic or
heteroaromatic ring system with one another; [0017] m, n is on each
occurrence, identically or differently, 0 or 1, where m=n=1 if L
stands for O, S or N(Ar).
[0018] An aryl group in the sense of this invention contains 6 to
60 C atoms; a heteroaryl group in the sense of this invention
contains 1 to 59 C atoms and at least one heteroatom, with the
proviso that the sum of C atoms and heteroatoms is at least 5. The
heteroatoms are preferably selected from N, O and/or S. An aryl
group or heteroaryl group here is taken to mean either a simple
aromatic ring, i.e. benzene, or a simple heteroaromatic ring, for
example pyridine, pyrimidine, thiophene, etc., or a condensed
(fused) aryl or heteroaryl group, for example naphthalene,
anthracene, phenanthrene, quinoline, isoquinoline, etc. Aromatic
rings linked to one another by a single bond, such as, for example,
biphenyl or bipyridine, are, by contrast, not referred to as an
aryl or heteroaryl group, but instead as an aromatic or
heteroaromatic ring system.
[0019] An aromatic ring system in the sense of this invention
contains 6 to 60 C atoms in the ring system. A heteroaromatic ring
system in the sense of this invention contains 1 to 59 C atoms and
at least one heteroatom in the ring system, with the proviso that
the sum of C atoms and heteroatoms is at least 5. The heteroatoms
are preferably selected from N, O and/or S. An aromatic or
heteroaromatic ring system in the sense of this invention is also
intended to be taken to mean, in particular, a system in which, in
addition, a plurality of aryl and/or heteroaryl groups are linked
to one another directly or via a carbon atom. Thus, for example,
systems such as biphenyl, terphenyl, fluorene, indenofluorene,
9,9'-spirobifluorene, 9,9-diarylfluorene, etc., in particular, are
also intended to be taken to be aromatic ring systems in the sense
of this invention.
[0020] For the purposes of the present invention, an aromatic or
heteroaromatic ring system which has not more than two six-membered
rings condensed directly onto one another is taken to mean an
aromatic ring system which either contains only non-condensed aryl
or heteroaryl groups, such as, for example, phenyl or pyridine, or
which contains aryl or heteroaryl groups having precisely two
aromatic six-membered rings condensed directly onto one another,
such as, for example, naphthalene or quinoline, or which, if it
contains relatively large condensed aryl- or heteroaryl groups,
then only contains those in which not only six-membered aromatic
rings, but also five-membered aromatic rings, are condensed on and
in which not more than two six-membered rings are condensed
directly onto one another. Thus, for example, anthracene,
phenanthrene, pyrene, perylene, etc. are excluded from the
definition of Ar.sup.3, Ar.sup.4 and L, since three, four or five
aromatic six-membered rings therein are condensed directly onto one
another; by contrast, fluorene, spirobifluorene, indenofluorene,
carbazole, indenocarbazole or indolocarbazole, for example, are
encompassed by the definition of Ar.sup.3, Ar.sup.4 and L, since in
no aromatic six-membered rings in these groups are condensed
directly onto one another, but instead only saturated (aliphatic)
five-membered rings or heteroaromatic five-membered rings. This
restriction regarding the condensed six-membered aryl groups is due
to the fact that the triplet energy in systems having more than two
six-membered rings condensed directly onto one another is
significantly lower, meaning that such materials are not very
suitable as matrix material for triplet emitters.
[0021] For the purposes of the present invention, an aliphatic
hydrocarbon radical or an alkyl group or an alkenyl or alkynyl
group, which may typically contain 1 to 40 or also 1 to 20 C atoms
and in which, in addition, individual H atoms or CH.sub.2 groups
may be substituted by the above-mentioned groups, is preferably
taken to mean the radicals methyl, ethyl, n-propyl, i-propyl,
n-butyl, i-butyl, s-butyl, t-butyl, 2-methylbutyl, n-pentyl,
s-pentyl, neopentyl, cyclopentyl, n-hexyl, neohexyl, cyclohexyl,
n-heptyl, cycloheptyl, n-octyl, cyclooctyl, 2-ethylhexyl,
trifluoromethyl, pentafluoroethyl, 2,2,2-trifluoroethyl, ethenyl,
propenyl, butenyl, pentenyl, cyclopentenyl, hexenyl, cyclohexenyl,
heptenyl, cycloheptenyl, octenyl, cyclooctenyl, ethynyl, propynyl,
butynyl, pentynyl, hexynyl, heptynyl and octynyl. An alkoxy group
having 1 to 40 C atoms is preferably taken to mean methoxy,
trifluoromethoxy, ethoxy, n-propoxy, i-propoxy, n-butoxy, i-butoxy,
s-butoxy, t-butoxy, n-pentoxy, s-pentoxy, 2-methylbutoxy, n-hexoxy,
cyclohexyloxy, n-heptoxy, cycloheptyloxy, n-octyloxy,
cyclooctyloxy, 2-ethylhexyloxy, pentafluoroethoxy and
2,2,2-trifluoroethoxy. A thioalkyl group having 1 to 40 C atoms is
taken to mean, in particular, methylthio, ethylthio, n-propylthio,
i-propylthio, n-butylthio, i-butylthio, s-butylthio, t-butylthio,
n-pentylthio, s-pentylthio, n-hexylthio, cyclohexylthio,
n-heptylthio, cycloheptylthio, n-octylthio, cyclooctylthio,
2-ethylhexylthio, trifluoromethylthio, pentafluoroethylthio,
2,2,2-trifluoroethylthio, ethenylthio, propenylthio, butenylthio,
pentenylthio, cyclopentenylthio, hexenylthio, cyclohexenylthio,
heptenylthio, cycloheptenylthio, octenylthio, cyclooctenylthio,
ethynylthio, propynylthio, butynylthio, pentynylthio, hexynylthio,
heptynylthio or octynylthio. In general, alkyl, alkoxy or thioalkyl
groups in accordance with the present invention may be
straight-chain, branched or cyclic, where one or more non-adjacent
CH.sub.2 groups may be replaced by the above-mentioned groups;
furthermore, one or more H atoms may also be replaced by D, F, Cl,
Br, I, CN or NO.sub.2, preferably F, Cl or CN, furthermore
preferably F or CN, particularly preferably CN.
[0022] An aromatic or heteroaromatic ring system having 5-80
aromatic ring atoms, which may also in each case be substituted by
the above-mentioned radicals R.sup.2 or a hydrocarbon radical and
which may be linked via any desired positions on the aromatic or
heteroaromatic ring system, is taken to mean, in particular, groups
derived from benzene, naphthalene, anthracene, benzanthracene,
phenanthrene, benzphenanthrene, pyrene, chrysene, perylene,
fluoranthene, naphthacene, pentacene, benzopyrene, biphenyl,
biphenylene, terphenyl, triphenylene, fluorene, spirobifluorene,
dihydrophenanthrene, dihydropyrene, tetrahydropyrene, cis- or
transindenofluorene, cis- or trans-indenocarbazole, cis- or
trans-indolocarbazole, truxene, isotruxene, spirotruxene,
spiroisotruxene, furan, benzofuran, isobenzofuran, dibenzofuran,
thiophene, benzothiophene, isobenzothiophene, dibenzothiophene,
pyrrole, indole, isoindole, carbazole, pyridine, quinoline,
isoquinoline, acridine, phenanthridine, benzo-5,6-quinoline,
benzo-6,7-quinoline, benzo-7,8-quinoline, phenothiazine,
phenoxazine, pyrazole, indazole, imidazole, benzimidazole,
naphthimidazole, phenanthrimidazole, pyridimidazole,
pyrazinimidazole, quinoxalinimidazole, oxazole, benzoxazole,
naphthoxazole, anthroxazole, phenanthroxazole, isoxazole,
1,2-thiazole, 1,3-thiazole, benzothiazole, pyridazine,
hexaazatriphenylene, benzopyridazine, pyrimidine, benzopyrimidine,
quinoxaline, 1,5diazaanthracene, 2,7-diazapyrene, 2,3-diazapyrene,
1,6-diazapyrene, 1,8diazapyrene, 4,5-diazapyrene,
4,5,9,10-tetraazaperylene, pyrazine, phenazine, phenoxazine,
phenothiazine, fluorubin, naphthyridine, azacarbazole,
benzocarboline, phenanthroline, 1,2,3-triazole, 1,2,4-triazole,
benzotriazole, 1,2,3-oxadiazole, 1,2,4-oxadiazole,
1,2,5-oxadiazole, 1,3,4-oxadiazole, 1,2,3-thiadiazole,
1,2,4-thiadiazole, 1,2,5-thiadiazole, 1,3,4-thiadiazole,
1,3,5-triazine, 1,2,4-triazine, 1,2,3-triazine, tetrazole,
1,2,4,5-tetrazine, 1,2,3,4-tetrazine, 1,2,3,5-tetrazine, purine,
pteridine, indolizine and benzothiadiazole or groups derived from
combinations of these systems.
[0023] In a preferred embodiment of the invention, Ar.sup.1 and
Ar.sup.2 are not connected via a single bond and thus preferably,
together with the nitrogen to which they are bonded, do not
represent a carbazole or carbazole derivative.
[0024] Preferred embodiments of the group of the formula (2) are,
for Ar.sup.5, selected from the group consisting of 1,3,5-triazine,
1,2,4-triazine, pyrazine, pyrimidine and pyridazine and, for
Ar.sup.6, from the group consisting of 1,3,5-triazine,
1,2,4-triazine, pyrazine, pyrimidine, pyridazine, pyridine, and
phenyl, where these groups may in each case be substituted by one
or more radicals R. The radical R here is as defined above and, if
Ar.sup.5 stands for a triazine, does not represent an alkoxy group,
thioalkoxy group, chlorine or substituted or unsubstituted amino
group.
[0025] In a preferred embodiment of the invention, the group
Ar.sup.6 contains at least one nitrogen in the ring.
[0026] In a particularly preferred embodiment of the invention, two
or three groups X in each group of the formula (2) stand,
identically or differently on each occurrence, for N, and the
remaining groups X stand for CR.
[0027] Preferred embodiments of the groups of the formula (2) which
stand for Ar.sup.5 are therefore, identically or differently on
each occurrence, the groups of the following formulae (3) to
(11),
##STR00003##
where the symbols used have the meanings given above; the dashed
bond here indicates the position of the bond from the group to the
nitrogen.
[0028] Preferred groups Ar.sup.6, apart from the groups of the
formulae (3) to (11) shown above, are the groups of the following
formulae (12) to (15),
##STR00004##
where the symbols used have the meanings given above; the dashed
bond here indicates the position of the bond from the group to the
nitrogen.
[0029] The groups Ar.sup.5 of the above-mentioned formulae (3) to
(11) can be combined with one another as desired with the groups
Ar.sup.6 of the above-mentioned formulae (3) to (15). The groups of
the formulae (3), (6), (7) and (8) are particularly preferred.
[0030] Preferred groups --NAr.sup.5Ar.sup.6 in compounds of the
formula (1) are the groups of the following formulae (16) to
(27):
##STR00005## ##STR00006## ##STR00007##
where the symbols used have the meanings given above, and the
dashed bond indicates the bond from this group to L or
Ar.sup.4.
[0031] In a preferred embodiment of the invention, Ar.sup.1 and
Ar.sup.2 stand, identically or differently on each occurrence, for
an aromatic or heteroaromatic ring system having 5 to 30 aromatic
ring atoms, particularly preferably having 5 to 24 aromatic ring
atoms, in particular for an aromatic ring system, which may in each
case also be substituted by one or more radicals R. The aromatic or
heteroaromatic ring system here preferably contains not more than
three, in particular not more than two, aromatic six-membered rings
condensed directly onto one another. The groups Ar.sup.1 and
Ar.sup.2 are preferably selected, identically or differently on
each occurrence, from the following formulae (28) to (42),
##STR00008## ##STR00009## ##STR00010##
where the symbols used have the meanings given above, and the
dashed bond indicates the bond from this group to the nitrogen.
[0032] The above-mentioned formulae (28) to (42) can be combined
with one another as desired. The groups of the formulae (28), (29),
(30), (33), (35), (36), (37) and (42) are particularly
preferred.
[0033] In a preferred embodiment of the invention, at least one
group Ar.sup.1 or Ar.sup.2 is a phenyl group or a meta- or
para-biphenyl group, which may be substituted by one or more
radicals R, i.e. a group of the above-mentioned formulae (28), (29)
or (30).
[0034] Examples of preferred groups --NAr.sup.1Ar.sup.2 in
compounds of the formula (1) are the groups of the following
formulae (43) to (50):
##STR00011## ##STR00012## ##STR00013##
where the symbols used have the meanings given above, and the
dashed bond indicates the bond from this group to Ar.sup.3 or to
L.
[0035] In a further preferred embodiment of the invention, if L is
linked directly to one or both nitrogen atoms, i.e. if n=0 and/or
m=0, L is a divalent straight-chain alkylene or alkylidene group
having 1 to 10 C atoms, in particular 1 to 5 C atoms, or a branched
or cyclic alkylene or alkylidene group having 3 to 10 C atoms, in
particular 3 to 6 C atoms, which may be substituted by in each case
one or more radicals R, where one or more CH.sub.2 groups which are
preferably not bonded directly to N and are preferably not adjacent
may be replaced by Si(R).sub.2, C.dbd.O, P(.dbd.O)R, S.dbd.O,
SO.sub.2, --O--, --S-- or --CONR-- and where one or more H atoms
may be replaced by D or F, or a divalent aromatic or heteroaromatic
ring system having 5 to 24 aromatic ring atoms, which may also be
substituted by one or more radicals R, or Si(R).sub.2, C(.dbd.O),
S(.dbd.O), SO.sub.2, P(.dbd.O)R or a combination of two or three of
these systems. If L is not bonded directly to N, i.e. if m=n=1, L
is, apart from the preferred embodiments mentioned above,
preferably selected from O, S or N(Ar). L here, as defined above,
does not contain any aryl groups having more than two aromatic
six-membered rings condensed directly onto one another. L also
preferably contains no naphthyl groups or other aryl groups having
two aromatic six-membered rings condensed directly onto one
another.
[0036] In a particularly preferred embodiment of the invention, L
is, if L is linked directly to one or both nitrogen atoms, i.e. if
n=0 and/or m=0, a divalent aromatic or heteroaromatic ring system
having 6 to 24 aromatic ring atoms, which may be substituted by one
or more radicals R, or Si(R).sub.2 or C(.dbd.O). If L is not bonded
directly to N, i.e. if m=n=1, L is, apart from the particularly
preferred embodiments mentioned above, particularly preferably
selected from O, S or N(Ar).
[0037] If L stands for an aromatic or heteroaromatic ring system, L
is then preferably selected from structures of the following
formulae (51) to (144),
##STR00014## ##STR00015## ##STR00016## ##STR00017## ##STR00018##
##STR00019## ##STR00020## ##STR00021## ##STR00022## ##STR00023##
##STR00024##
where the symbols used have the meanings given above, and the
dashed bonds indicate the bonds to N or Ar.sup.3 or Ar.sup.4. If a
precise position of the bond is not indicated, this means that the
bond can be in any desired position.
[0038] In a further preferred embodiment of the invention, Ar.sup.3
and Ar.sup.4 are selected, identically or differently on each
occurrence, from structures of the above-mentioned formulae (51) to
(144).
[0039] In a further preferred embodiment of the invention, the
indices m and n=1, i.e. the bridging unit has the structure
--Ar.sup.3-L-Ar.sup.4--. The bridging unit L here preferably has a
structure of the following formula (145):
--(CR.sub.2).sub.p--(Y).sub.q-- formula (145)
where R has the meaning given above, and furthermore: [0040] Y is,
identically or differently on each occurrence, CR.sub.2, SiR.sub.2,
GeR.sub.2, S, O or NR; [0041] p is a number from 0 to 14,
preferably 0, 1, 2, 3, 4, 5 or 6; [0042] q is 0, 1, 2, 3 or 4,
preferably 0, 1 or 2; [0043] p+q>0; [0044] with the proviso that
a plurality of heteroatoms are not bonded directly to one
another.
[0045] Examples of preferred groups Ar.sup.3-L-Ar.sup.4 are the
following groups:
##STR00025## ##STR00026## ##STR00027## ##STR00028## ##STR00029##
##STR00030## ##STR00031## ##STR00032## ##STR00033##
[0046] In a preferred embodiment of the invention, R is selected,
identically or differently on each occurrence, from the group
consisting of H, D, F, Cl, Br, CN, C(.dbd.O)Ar, a straight-chain
alkyl or alkoxy group having 1 to 10 C atoms or a branched or
cyclic alkyl or alkoxy group having 3 to 10 C atoms, each of which
may be substituted by one or more radicals R.sup.1, where one or
more non-adjacent CH.sub.2 groups may be replaced by 0 and where
one or more H atoms may be replaced by D or F, an aromatic or
heteroaromatic ring system having 5 to 30 aromatic ring atoms,
which may in each case be substituted by one or more radicals
R.sup.1, or an aryloxy or heteroaryloxy group having 5 to 30
aromatic ring atoms, which may be substituted by one or more
radicals R.sup.1.
[0047] In a particularly preferred embodiment of the invention, R
is selected, identically or differently on each occurrence, from
the group consisting of H, D, F, CN, a straight-chain alkyl group
having 1 to 10 C atoms or a branched or cyclic alkyl group having 3
to 10 C atoms, each of which may be substituted by one or more
radicals R.sup.1, where one or more H atoms may be replaced by D or
F, or an aromatic or heteroaromatic ring system having 5 to 18
aromatic ring atoms, which may in each case be substituted by one
or more radicals R.sup.1.
[0048] The radical R which is bonded to Ar.sup.5 or Ar.sup.6, i.e.
which is bonded to the structure of the formula (2), is
particularly preferably selected, identically or differently on
each occurrence, from the group consisting of H, D or an aromatic
or heteroaromatic ring system having 6 to 18 aromatic ring atoms,
where the aromatic or heteroaromatic ring system is selected, in
particular, from the group consisting of phenyl, ortho-, meta- or
para-biphenyl, ortho-, meta-, para- or branched terphenyl and
quaterphenyl.
[0049] For compounds which are processed by vacuum evaporation, the
alkyl groups preferably have not more than four C atoms,
particularly preferably not more than 1 C atom. For compounds which
are processed from solution, compounds which are substituted by
alkyl groups having up to 10 C atoms or which are substituted by
oligoarylene groups, for example ortho-, meta-, para- or branched
terphenyl or quaterphenyl groups, are also suitable.
[0050] In a preferred embodiment of the invention, R.sup.1 is
selected, identically or differently on each occurrence, from the
group consisting of H, D, F, CN, a straight-chain alkyl group
having 1 to 10 C atoms or a branched or cyclic alkyl group having 3
to 10 C atoms, where one or more H atoms may be replaced by D or F,
or an aromatic or heteroaromatic ring system having 5 to 30
aromatic ring atoms, which may in each case be substituted by one
or more radicals R.sup.2.
[0051] In a particularly preferred embodiment of the invention,
R.sup.1 is selected, identically or differently on each occurrence,
from the group consisting of H, D, F, CN, a straight-chain alkyl
group having 1 to 5 C atoms or a branched or cyclic alkyl group
having 3 to 5 C atoms, or an aromatic or heteroaromatic ring system
having 5 to 18 aromatic ring atoms.
[0052] Examples of preferred compounds of the above-mentioned
embodiments are the compounds of the following structures.
##STR00034## ##STR00035## ##STR00036## ##STR00037## ##STR00038##
##STR00039## ##STR00040## ##STR00041## ##STR00042## ##STR00043##
##STR00044## ##STR00045## ##STR00046## ##STR00047## ##STR00048##
##STR00049## ##STR00050## ##STR00051## ##STR00052##
[0053] The compounds according to the invention can be prepared by
synthetic steps known to the person skilled in the art, such as,
for example, bromination, Ullmann arylation, Hartwig-Buchwald
coupling, etc., as depicted for two example compounds in Scheme 1
and 2. Further derivatives of the compounds according to the
invention can be prepared entirely analogously. Thus, for example,
a group L, L-Ar.sup.4, Ar.sup.4 or Ar.sup.3-L-Ar.sup.4 which is
simultaneously substituted by a reactive leaving group, for example
chlorine, bromine or iodine, and by an amino group can be reacted
with a derivative of the group Ar.sup.5 which is substituted by a
reactive leaving group, for example fluorine, chlorine, bromine or
iodine. This reaction can be carried out either as a nucleophilic
aromatic substitution, if necessary with addition of a base, or in
a metal-catalysed coupling reaction, for example a Hartwig-Buchwald
coupling. The group Ar.sup.6 can be introduced entirely analogously
in a further step. The reactive leaving group on Ar.sup.3 or L can
then be reacted, in a subsequent step, with a compound
Ar.sup.1Ar.sup.2NH in a metal-promoted coupling reaction, for
example an Ullmann coupling or a Hartwig-Buchwald coupling. The
reactive leaving group on L can furthermore be reacted, in a
subsequent step, with a compound Ar.sup.1Ar.sup.2NAr.sup.4, or the
reactive leaving group on Ar.sup.4 can be reacted, in a subsequent
step, with a compound Ar.sup.1Ar.sup.2NAr.sup.3 or
Ar.sup.1Ar.sup.2NAr.sup.3L, which is substituted by a reactive
group, for example a boronic acid or a boronic acid ester, to give
the compound of the formula (1) according to the invention.
Suitable coupling reactions are, for example, Suzuki coupling or
Stille coupling.
##STR00053##
##STR00054##
[0054] The present invention therefore furthermore relates to a
process for the preparation of a compound of the formula (1),
comprising the reaction steps: [0055] a) synthesis of a compound
G-(Ar.sup.3).sub.n-L-(Ar.sup.4).sub.m--NAr.sup.5Ar.sup.6 by
reaction of a compound
G-(Ar.sup.3).sub.n-L-(Ar.sup.4).sub.m--NH.sub.2 with a compound
G-Ar.sup.5 and G-Ar.sup.6, optionally with addition of a base
and/or a catalyst, where G stands for a reactive leaving group, in
particular fluorine, chlorine, bromine or iodine; and [0056] b)
introduction of the group Ar.sup.1Ar.sup.2N-- by coupling a group
Ar.sup.1Ar.sup.2NH to Ar.sup.3 or L, for example by Ullmann or
Hartwig-Buchwald coupling, or by coupling a group
Ar.sup.1Ar.sup.2--N--Ar.sup.3-G to L, for example by Suzuki
coupling.
[0057] The reactive leaving group in step b) is preferably selected
from Cl, Br, I, boronic acid or boronic acid derivatives, in
particular boronic acid esters, triflate or tosylate.
[0058] The compounds according to the invention described above, in
particular compounds which are substituted by reactive leaving
groups, such as bromine, iodine, chlorine, boronic acid or boronic
acid ester, or by reactive, polymerisable groups, such as olefins
or oxetanes, can be used as monomers for the preparation of
corresponding oligomers, dendrimers or polymers. The
oligomerisation or polymerisation here is preferably carried out
via the halogen functionality or the boronic acid functionality or
via the polymerisable group. It is furthermore possible to
crosslink the polymers via groups of this type. The compounds and
polymers according to the invention can be employed as crosslinked
or uncrosslinked layer.
[0059] The invention therefore furthermore relates to oligomers,
polymers or dendrimers comprising one or more of the compounds
according to the invention mentioned above, where one or more bonds
are present from the compound according to the invention to the
polymer, oligomer or dendrimer. Depending on the linking of the
compound according to the invention, this therefore forms a side
chain of the oligomer or polymer or is linked in the main chain.
The polymers, oligomers or dendrimers may be conjugated, partially
conjugated or non-conjugated. The oligomers or polymers may be
linear, branched or dendritic. The same preferences as described
above apply to the recurring units of the compounds according to
the invention in oligomers, dendrimers and polymers.
[0060] For the preparation of the oligomers or polymers, the
monomers according to the invention are homopolymerised or
copolymerised with further monomers. Preference is given to
homopolymers or copolymers, where the units of the formula (1) are
present in a proportion of 0.01 to 99.9 mol %, preferably 5 to 90
mol %, particularly preferably 20 to 80 mol %. Suitable and
preferred comonomers which form the polymer backbone are selected
from fluorenes (for example in accordance with EP 842208 or WO
2000/22026), spirobifluorenes (for example in accordance with EP
707020, EP 894107 or WO 2006/061181), para-phenylenes (for example
in accordance with WO 92/18552), carbazoles (for example in
accordance with WO 2004/070772 or WO 2004/113468), thiophenes (for
example in accordance with EP 1028136), dihydrophenanthrenes (for
example in accordance with WO 2005/014689), cis- and
trans-indenofluorenes (for example in accordance with WO
2004/041901 or WO 2004/113412), ketones (for example in accordance
with WO 2005/040302), phenanthrenes (for example in accordance with
WO 2005/104264 or WO 2007/017066) or also a plurality of these
units. The polymers, oligomers and dendrimers may also comprise
further units, for example hole-transport units, in particular
those based on triarylamines, and/or electron-transport units. In
addition, the polymers can either comprise triplet emitters in
copolymerised form or mixed in as a blend. Precisely the
combination of units of the formula (1) with triplet emitters gives
particularly good results.
[0061] Furthermore, the compounds of the formula (1) may also be
functionalised further and thus converted into extended structures.
An example which may be mentioned here is the reaction with
arylboronic acids by the Suzuki method or with primary or secondary
amines by the Hartwig-Buchwald method. Thus, the compounds of the
formula (1) can also be bonded directly to phosphorescent metal
complexes or also to other metal complexes.
[0062] The compounds according to the invention are suitable for
use in an electronic device. An electronic device here is taken to
mean a device which comprises at least one layer which comprises at
least one organic compound. However, the component here may also
comprise inorganic materials or also layers built up entirely from
inorganic materials.
[0063] The present invention therefore furthermore relates to the
use of the compounds according to the invention mentioned above in
an electronic device, in particular in an organic
electroluminescent device.
[0064] The present invention again furthermore relates to an
electronic device comprising at least one of the compounds
according to the invention mentioned above. The preferences stated
above likewise apply to the electronic devices.
[0065] The electronic device is preferably selected from the group
consisting of organic electroluminescent devices (organic
light-emitting diodes, OLEDs), organic integrated circuits (O-ICs),
organic field-effect transistors (O-FETs), organic thin-film
transistors (O-TFTs), organic light-emitting transistors (O-LETs),
organic solar cells (O-SCs), organic dye-sensitized solar cells
(ODSSCs), organic optical detectors, organic photoreceptors,
organic field-quench devices (O-FQDs), light-emitting
electrochemical cells (LECs), organic laser diodes (O-lasers) and
"organic plasmon emitting devices" (D. M. Koller et al., Nature
Photonics 2008, 1-4), but preferably organic electroluminescent
devices (OLEDs), particularly preferably phosphorescent OLEDs.
[0066] The organic electroluminescent devices and the
light-emitting electrochemical cells can be used for various
applications, for example for monochromatic or polychromatic
displays, for lighting applications or for medical or cosmetic
applications, for example in phototherapy.
[0067] The organic electroluminescent device comprises a cathode,
an anode and at least one emitting layer. Apart from these layers,
it may also comprise further layers, for example in each case one
or more hole-injection layers, hole-transport layers, hole-blocking
layers, electron-transport layers, electron-injection layers,
exciton-blocking layers, electron-blocking layers and/or
charge-generation layers. It is likewise possible for interlayers,
which have, for example, an exciton-blocking function, to be
introduced between two emitting layers. However, it should be
pointed out that each of these layers does not necessarily have to
be present.
[0068] The organic electroluminescent device may comprise one
emitting layer or a plurality of emitting layers. If a plurality of
emission layers are present, these preferably have in total a
plurality of emission maxima between 380 nm and 750 nm, resulting
overall in white emission, i.e. various emitting compounds which
are able to fluoresce or phosphoresce are used in the emitting
layers. Particular preference is given to systems having three
emitting layers, where the three layers exhibit blue, green and
orange or red emission (for the basic structure see, for example,
WO 05/011013). It is possible here for all emitting layers to be
fluorescent or for all emitting layers to be phosphorescent or for
one or more emitting layers to be fluorescent and one or more other
layers to be phosphorescent.
[0069] The compound according to the invention in accordance with
the embodiments indicated above can be employed in various layers,
depending on the precise structure. Preference is given to an
organic electroluminescent device comprising a compound of the
formula (1) as matrix material for fluorescent or phosphorescent
emitters, in particular for phosphorescent emitters, and/or in a
hole-blocking layer and/or in an electron-transport layer and/or in
an electron-blocking or exciton-blocking layer and/or in a
hole-transport layer, depending on the precise substitution. The
preferred embodiments indicated above also apply to the use of the
materials in organic electronic devices.
[0070] In a particularly preferred embodiment of the invention, the
compound of the formula (1) is employed as matrix material for a
fluorescent or phosphorescent compound, in particular for a
phosphorescent compound, in an emitting layer. The organic
electroluminescent device here may comprise one emitting layer or a
plurality of emitting layers, where at least one emitting layer
comprises at least one compound according to the invention as
matrix material.
[0071] If the compound of the formula (1) is employed as matrix
material for an emitting compound in an emitting layer, it is
preferably employed in combination with one or more phosphorescent
materials (triplet emitters). Phosphorescence in the sense of this
invention is taken to mean the luminescence from an excited state
of relatively high spin multiplicity, i.e. a spin state>1, in
particular from an excited triplet state. For the purposes of this
application, all luminescent complexes containing transition metals
or lanthanoids, in particular all luminescent iridium, platinum and
copper complexes, are to be regarded as phosphorescent
compounds.
[0072] The mixture of the compound of the formula (1) and the
emitting compound comprises between 99 and 1% by weight, preferably
between 98 and 10% by weight, particularly preferably between 97
and 60% by weight, in particular between 95 and 80% by weight, of
the compound of the formula (1), based on the entire mixture
comprising emitter and matrix material. Correspondingly, the
mixture comprises between 1 and 99% by weight, preferably between 2
and 90% by weight, particularly preferably between 3 and 40% by
weight, in particular between 5 and 20% by weight, of the emitter,
based on the entire mixture comprising emitter and matrix
material.
[0073] A further preferred embodiment of the present invention is
the use of the compound of the formula (1) as matrix material for a
phosphorescent emitter in combination with a further matrix
material. Particularly suitable matrix materials which can be
employed in combination with the compounds of the formulae (1) are
aromatic ketones, aromatic phosphine oxides or aromatic sulfoxides
or sulfones, for example in accordance with WO 2004/013080, WO
2004/093207, WO 2006/005627 or WO 2010/006680, triarylamines,
carbazole derivatives, for example CBP(N,N-biscarbazolylbiphenyl),
m-CBP or the carbazole derivatives disclosed in WO 05/039246, US
2005/0069729, JP 2004/288381, EP 1205527 or WO 2008/086851,
indolocarbazole derivatives, example in accordance with WO
2007/063754 or WO 2008/056746, indenocarbazole derivatives, for
example in accordance with the unpublished applications DE
102009023155.2 or DE 102009031021.5, azacarbazole derivatives, for
example in accordance with EP 1617710, EP 1617711, EP 1731584, JP
2005/347160, bipolar matrix materials, for example in accordance
with WO 2007/137725, silanes, for example in accordance with WO
2005/111172, azaboroles or boronic esters, for example in
accordance with WO 2006/117052, triazine derivatives, for example
in accordance with the unpublished application DE 102008036982.9,
WO 2007/063754 or WO 2008/056746, zinc complexes, for example in
accordance with EP 652273 or WO 2009/062578, fluorene derivatives,
for example in accordance with WO 2009/124627, diazasilole or
tetraazasilole derivatives, for example in accordance with WO
2010/054729, diazaphosphole derivatives, for example in accordance
with WO 2010/054730, or bridged carbazole derivatives, for example
in accordance with US 2009/0136779 or in accordance with the
unpublished application DE 102009048791.3. It is furthermore
possible to use an electronically neutral co-host which has neither
hole-transporting nor electron-transporting properties, as
described, for example, in WO 2010/108579.
[0074] It is likewise possible to use two or more phosphorescent
emitters in the mixture. The emitter, which emits at relatively
short wavelength, is used here as co-host in the mixture.
[0075] Suitable phosphorescent compounds (=triplet emitters) are,
in particular, compounds which emit light, preferably in the
visible region, on suitable excitation and in addition contain at
least one atom having an atomic number greater than 20, preferably
greater than 38 and less than 84, particularly preferably greater
than 56 and less than 80, in particular a metal having this atomic
number. The phosphorescence emitters used are preferably compounds
which contain copper, molybdenum, tungsten, rhenium, ruthenium,
osmium, rhodium, iridium, palladium, platinum, silver, gold or
europium, in particular compounds which contain iridium, platinum
or copper.
[0076] Examples of the emitters described above are revealed by the
applications WO 2000/70655, WO 2001/41512, WO 2002/02714, WO
2002/15645, EP 1191613, EP 1191612, EP 1191614, WO 2005/033244, WO
2005/019373, US 2005/0258742, WO 2009/146770, WO 2010/015307, WO
2010/031485, WO 2010/054731, WO 2010/054728, WO 2010/086089, WO
2010/099852 and WO 2010/102709. In general, all phosphorescent
complexes as used in accordance with the prior art for
phosphorescent OLEDs and as are known to the person skilled in the
art in the area of organic electroluminescence are suitable, and
the person skilled in the art will be able to use further
phosphorescent complexes without inventive step.
[0077] Examples of suitable phosphorescent compounds are listed in
the following table.
TABLE-US-00001 ##STR00055## ##STR00056## ##STR00057## ##STR00058##
##STR00059## ##STR00060## ##STR00061## ##STR00062## ##STR00063##
##STR00064## ##STR00065## ##STR00066## ##STR00067## ##STR00068##
##STR00069## ##STR00070## ##STR00071## ##STR00072## ##STR00073##
##STR00074## ##STR00075## ##STR00076## ##STR00077## ##STR00078##
##STR00079## ##STR00080## ##STR00081## ##STR00082## ##STR00083##
##STR00084## ##STR00085## ##STR00086## ##STR00087## ##STR00088##
##STR00089## ##STR00090## ##STR00091## ##STR00092## ##STR00093##
##STR00094## ##STR00095## ##STR00096## ##STR00097## ##STR00098##
##STR00099## ##STR00100## ##STR00101## ##STR00102## ##STR00103##
##STR00104## ##STR00105## ##STR00106## ##STR00107## ##STR00108##
##STR00109## ##STR00110## ##STR00111## ##STR00112## ##STR00113##
##STR00114## ##STR00115## ##STR00116## ##STR00117## ##STR00118##
##STR00119## ##STR00120## ##STR00121## ##STR00122## ##STR00123##
##STR00124## ##STR00125## ##STR00126## ##STR00127## ##STR00128##
##STR00129## ##STR00130## ##STR00131## ##STR00132## ##STR00133##
##STR00134## ##STR00135## ##STR00136## ##STR00137## ##STR00138##
##STR00139## ##STR00140## ##STR00141## ##STR00142## ##STR00143##
##STR00144## ##STR00145## ##STR00146## ##STR00147## ##STR00148##
##STR00149## ##STR00150## ##STR00151## ##STR00152## ##STR00153##
##STR00154## ##STR00155## ##STR00156## ##STR00157## ##STR00158##
##STR00159## ##STR00160## ##STR00161## ##STR00162## ##STR00163##
##STR00164## ##STR00165## ##STR00166## ##STR00167## ##STR00168##
##STR00169## ##STR00170## ##STR00171## ##STR00172## ##STR00173##
##STR00174## ##STR00175## ##STR00176## ##STR00177## ##STR00178##
##STR00179##
##STR00180## ##STR00181## ##STR00182## ##STR00183## ##STR00184##
##STR00185## ##STR00186## ##STR00187## ##STR00188## ##STR00189##
##STR00190## ##STR00191## ##STR00192## ##STR00193## ##STR00194##
##STR00195## ##STR00196## ##STR00197##
[0078] In a further embodiment of the invention, the organic
electroluminescent device does not comprise a separate
hole-injection layer and/or hole-transport layer and/or
hole-blocking layer and/or electron-transport layer, i.e. the
emitting layer is directly adjacent to the hole-injection layer or
the anode, and/or the emitting layer is directly adjacent to the
electron-transport layer or the electron-injection layer or the
cathode, as described, for example, in WO 2005/053051. It is
furthermore possible to use a metal complex which is identical or
similar to the metal complex in the emitting layer as
hole-transport or hole-injection material directly adjacent to the
emitting layer, as described, for example, in WO 2009/030981.
[0079] In a further preferred embodiment of the invention, the
compound of the formula (1) is employed as electron-transport
material in an electron-transport or electron-injection layer. The
emitting layer here may be fluorescent or phosphorescent. If the
compound is employed as electron-transport material, it may be
preferred for it to be doped, for example with alkali-metal
complexes, such as, for example, Liq (lithium
hydroxyquinolinate).
[0080] In yet a further preferred embodiment of the invention, the
compound of the formula (1) is employed in a hole-blocking layer. A
hole-blocking layer is taken to mean a layer which is directly
adjacent to an emitting layer on the cathode side.
[0081] It is furthermore possible to use the compound of the
formula (1) both in a hole-blocking layer or electron-transport
layer and as matrix in an emitting layer.
[0082] In the further layers of the organic electroluminescent
device according to the invention, it is possible to use all
materials as usually employed in accordance with the prior art. The
person skilled in the art will therefore be able, without an
inventive step, to employ all materials known for organic
electroluminescent devices in combination with the compounds of the
formulae (1) according to the invention.
[0083] Preference is furthermore given to an organic
electroluminescent device, characterised in that one or more layers
are applied by means of a sublimation process, in which the
materials are vapour-deposited in vacuum sublimation units at an
initial pressure of usually less than 10.sup.-5 mbar, preferably
less than 10.sup.-6 mbar. However, it is also possible for the
initial pressure to be even lower, for example less than 10.sup.-7
mbar.
[0084] Preference is likewise given to an organic
electroluminescent device, characterised in that one or more layers
are applied by means of the OVPD (organic vapour phase deposition)
process or with the aid of carrier-gas sublimation, in which the
materials are applied at a pressure between 10.sup.-5 mbar and 1
bar. A special case of this process is the OVJP (organic vapour jet
printing) process, in which the materials are applied directly
through a nozzle and thus structured (for example M. S. Arnold et
al., Appl. Phys. Lett. 2008, 92, 053301).
[0085] Preference is furthermore given to an organic
electroluminescent device, characterised in that one or more layers
are produced from solution, such as, for example, by spin coating,
or by means of any desired printing process, such as, for example,
LITI (light induced thermal imaging, thermal transfer printing),
ink-jet printing, screen printing, flexographic printing or offset
printing. Soluble compounds, which are obtained, for example, by
suitable substitution, are necessary for this purpose. These
processes are also suitable for oligomers, dendrimers and polymers.
These processes are also particularly suitable for the compounds
according to the invention, since they generally have very good
solubility in organic solvents.
[0086] Also possible are hybrid processes, in which, for example,
one or more layers are applied from solution and one or more
further layers are applied by vapour deposition. Thus, for example,
the emitting layer can be applied from solution and the
electron-transport layer can be applied by vapour deposition.
[0087] These processes are generally known to the person skilled in
the art and can be applied by him without inventive step to organic
electroluminescent devices comprising the compounds according to
the invention.
[0088] Formulations of the compounds according to the invention are
necessary for the processing of the compounds according to the
invention from the liquid phase, for example by spin coating or by
printing processes. These formulations can be, for example,
solutions, dispersions or mini emulsions. It may be preferred to
use mixtures of two or more solvents for this purpose. Suitable and
preferred solvents are, for example, toluene, anisole, o-, m- or
p-xylene, methyl benzoate, dimethylanisole, mesitylene, tetralin,
veratrol, THF, methyl-THF, THP, chlorobenzene, dioxane or mixtures
of these solvents.
[0089] The present invention therefore furthermore relates to a
formulation, in particular a solution, dispersion or mini emulsion,
comprising at least one compound of the formula (1) or a
corresponding oligomer, polymer or dendrimer according to the
invention and at least one solvent, in particular an organic
solvent. The way in which such solutions can be prepared is known
to the person skilled in the art and is described, for example, in
WO 2002/072714, WO 2003/019694 and the literature cited
therein.
[0090] The present invention furthermore relates to mixtures
comprising at least one compound of the formula (1) or a
corresponding oligomer, polymer or dendrimer according to the
invention and at least one further compound. The further compound
can be, for example, a fluorescent or phosphorescent dopant if the
compound according to the invention is used as matrix material.
Suitable fluorescent and phosphorescent dopants are mentioned above
in connection with the organic electroluminescent devices and are
also preferred for the mixtures according to the invention.
[0091] The compounds according to the invention and the organic
electroluminescent devices according to the invention are
distinguished by the following surprising advantages over the prior
art: [0092] 1. The compounds according to the invention or
compounds of the formulae (1), employed as matrix material for
fluorescent or phosphorescent emitters, result in very high
efficiencies and long lifetimes. This applies, in particular, if
the compounds are employed as matrix material for a phosphorescent
emitter. [0093] 2. The compounds according to the invention or
compounds of the formulae (1) are suitable not only as matrix for
red- and green-phosphorescent compounds, but also for
blue-phosphorescent compounds. [0094] 3. The compounds according to
the invention or compounds of the formula (1) have a very small
separation between the S.sub.1 level, i.e. the first excited
singlet level, and the T.sub.1 level, i.e. the first excited
triplet level, and are therefore particularly suitable for use as
matrix in phosphorescent OLEDs. [0095] 4. The compounds according
to the invention, employed in organic electroluminescent devices,
result in high efficiencies and in steep current/voltage curves
with low use and operating voltages.
[0096] These above-mentioned advantages are not accompanied by an
impairment in the other electronic properties.
[0097] The invention is explained in greater detail by the
following examples, without wishing to restrict it thereby. The
person skilled in the art will be able to use the descriptions to
carry out the invention throughout the range disclosed and to
prepare further compounds according to the invention without
inventive step and use them in electronic devices or use the
process according to the invention.
EXAMPLES
[0098] The following syntheses are carried out under a
protective-gas atmosphere in dried solvents, unless indicated
otherwise.
Example 1
Synthesis of TMM2
##STR00198##
[0099] a)
(4-Bromophenyl)-(4,6-diphenyl-1,3,5-triazin-2-yl)amine
##STR00199##
[0101] 23.4 g (87.2 mmol) of 2-chloro-4,6-diphenyl-1,3,5-triazine
in 400 ml of toluene are added to a well-stirred solution of 15.0 g
(87.2 mmol) of 4-bromoaniline in 280 ml of pyridine and 400 ml of
toluene, and the mixture is subsequently stirred at room
temperature for 16 h. The solvent is subsequently removed in vacuo,
and the residue is purified by chromatography (heptane/ethyl
acetate 20:1). Yield: 21.1 g (52.3 mmol), 60%.
b) (4-Bromophenyl)bis-(4,6-diphenyl-1,3,5-triazin-2-yl)amine
##STR00200##
[0103] 0.32 g (8 mmol) of NaH (60% in oil) is initially introduced
in 100 ml of THF. A solution of 2.00 g (5 mmol) of the product from
a) in 50 ml of THF is added dropwise at room temperature. After 1
h, 1.35 g (5 mmol) of 2-chloro-4,6-diphenyl-1,3,5-triazine are
added, the mixture is heated under reflux for 8 h and stirred at RT
for 12 h. The solvent is subsequently removed in vacuo, and the
residue is purified by chromatography (heptane/ethyl acetate 20:1).
Yield: 0.71 g (1.2 mmol), 22%.
c) TMM2
##STR00201##
[0105] 0.95 g (1.5 mmol) of the product from b), 0.45 g (1.7 mmol)
of 4-diphenylaminophenylboronic acid and 0.81 g (3.75 mmol) of
tripotassium phosphate are suspended in 50 ml of toluene, 50 ml of
dioxane and 50 ml of water. 45.6 mg (0.15 mmol) of
tri-o-tolylphosphine and then 17 mg (0.075 mmol) of palladium(II)
acetate are added to this suspension, and the reaction mixture is
heated under reflux for 16 h. After cooling, the organic phase is
separated off, filtered through silica gel, washed three times with
20 ml of water each time and subsequently evaporated to dryness.
The residue is recrystallised from toluene and from
dichloromethane/isopropanol. The yield is 0.59 g (0.74 mmol),
corresponding to 49% of theory.
Example 2
Synthesis of TMM3
##STR00202##
[0106] a) Bis(4-bromophenyl)diphenylsilane
##STR00203##
[0108] 10.81 g (50 mmol) of 1,4-dibromobenzene are dissolved in 400
ml of dry THF and cooled to -78.degree. C. 20 ml (50 mmol) of
n-butyllithium are subsequently added dropwise at -78.degree. C.,
and, when the addition is complete, the mixture is stirred at
78.degree. C. for a further 1 h. 6.3 g (25 mmol) of
dichlorodiphenylsilane, dissolved in 80 ml of dry THF, are then
slowly added dropwise and allowed to come to room temperature
overnight. The reaction mixture is evaporated to dryness in a
rotary evaporator, and the solid is recrystallised from toluene and
then from n-butanol. The yield is 10 g (0.21 mmol), corresponding
to 81% of theory.
b)
2,2'-[(Diphenylsilylene)di-1,4-phenylene]bis(4,4,5,5-tetramethyl-1,3,2--
dioxaborolane)
##STR00204##
[0110] A mixture of bis(4-bromophenyl)diphenylsilane (28.2 g, 57
mmol), bis(pinacolato)diboron (16.0 g, 63 mmol), potassium acetate
(18.6 g, 0.19 mol), PdCl.sub.2(dppf).times.CH.sub.2Cl.sub.2 (0.75
g, 1 mmol) and dioxane (400 ml) is degassed for 30 min. The
reaction mixture is heated under reflux for 6 h. After cooling to
room temperature, the mixture is poured into ice-water (80 ml) and
extracted with toluene. The combined organic phases are dried over
sodium sulfate, and the solvent is distilled off under reduced
pressure, leaving a brown liquid. The end product is isolated as
pale-brown solid (30.2 g, 90%).
c) TMM3
##STR00205##
[0112] A mixture of 13.18 g (22.4 mmol) of
2'-[(diphenylsilylene)di-1,4-phenylene]-bis(4,4,5,5-tetramethyl-1,3,2-dio-
xaborolane), 7.2 g (11.2 mmol) of
(4-bromophenyl)bis(4,6-diphenyl-1,3,5-triazin-2-yl)amine and 3.9 g
(11.7 mmol) of (4-bromophenyl)diphenylamine in 250 ml of toluene
and 250 ml of dioxane is degassed by passing-through of N.sub.2 for
30 min. 252 mg (1.12 mmol) of Pd(OAc).sub.2 and 1.34 g (4.48 mmol)
of tris-o-tolylphosphine are then added, and the mixture is heated
at 80.degree. C. for 8 h. After cooling to room temperature, the
mixture is diluted with 100 ml of water and extracted with ethyl
acetate (3.times.50 ml). The combined organic phases are dried over
sodium sulfate, and the solvent is removed under reduced pressure.
The crude product is purified by flash chromatography over silica
and crystallisation (17 g, 67%).
Example 3
Synthesis of TMM4
##STR00206##
[0114] A mixture of
1,6-bis(p-bis[4,4,5,5-tetramethyl-1,3,2-dioxaborolane]phenyl)hexane
(11 g, 22.4 mmol),
(4-bromophenyl)bis-(4,6-diphenyl-1,3,5-triazin-2-yl)amine (7.2 g,
11.2 mmol) and (4-bromophenyl)diphenylamine (3.9 g, 11.7 mmol) in
250 ml of toluene and 250 ml of dioxane is degassed using N.sub.2
for 30 min. Pd(OAc).sub.2 (252 mg, 1.12 mmol) and
tris-o-tolylphosphine (1.34 g, 4.48 mmol) is then added, and the
mixture is heated at 80.degree. C. for 24 h. After cooling to room
temperature, the mixture is diluted with 100 ml of water and
extracted with ethyl acetate (3.times.50 ml). The combined organic
phases are dried over sodium sulfate, and the solvent is removed
under reduced pressure. The crude product is purified by flash
chromatography over silica and crystallisation (15 g, 64%).
Use Examples
Materials Used:
[0115] The following materials are used in the present invention:
TMM1 is a reference matrix material in accordance with the prior
art (WO 2008/086851). TMM2, TMM3 and TMM4 are matrix materials
according to the invention, the syntheses of which are described in
Examples 1 to 3. The abbreviation TMM here stands for triplet
matrix material. TEG1 is a phosphorescent emitter, where TEG stands
for triplet emitter green.
##STR00207## ##STR00208##
[0116] Polymer IL1, which is used as interlayer, is a copolymer of
the following monomers, which is synthesised by Suzuki coupling, as
disclosed in WO 2003/048225:
##STR00209##
Example 4
Measurement of the Triplet Level and Quantum-Chemical Simulations
for TMM1 to TMM6 and TEG1
[0117] The quantum-chemical simulations for TMM1 to TMM6 and TEG1
are carried out in Gaussian 03W (Gaussian Inc.): firstly, AM1 is
used in order to optimise the molecular geometry, and TD-DFT
(time-dependent density function theory) with correction functional
B3PW9 and base set 6-31 G(d) is used for the energy calculation,
which include the positions of HOMO and LUMO and the energies of
the triplet state and the excited singlet state. The first triplet
state and the first excited singlet state are the most important
states. These are denoted below by T1 and S1. The HOMO and LUMO
values are corrected by cyclic voltammetry (CV) as follows: a
series of materials are measured by CV and also calculated by
Gaussian 03W using the same method, for example using B3PW91 and
the same base set 6-31G(d). The calculated values are then
calibrated in accordance with the measured values. This calibration
factor is used for the further calculations.
[0118] The T1 levels of TMM1 to TMM4 are furthermore measured by
time-resolved spectroscopy at low temperature as follows: a film of
TMM1 to TMM4 is coated onto quartz in a thickness of 100 nm and
then excited using a YAG laser (355 nm) or an N.sub.2 laser (337
nm) at liquid-helium temperature (10 K). The delayed
photoluminescence spectrum after 10 .mu.s is recorded. The T1 level
is then determined by the onset of delayed photoluminescence.
[0119] The simulated and measured energy levels are summarised in
Table 1. The T1 level of TEG1 is derived from the onset of the
photoluminescence spectrum of TEG1 in toluene. The T1 levels of
TMM1 to TMM6, both the simulated and calculated values, are higher
than those of TEG1, which indicates that all these materials are
suitable matrix materials for TEG1.
[0120] However, the reference matrix TMM1 has a large band
separation and a large S1-T1 gap (about 0.43 eV), which can result
in difficulties with charge injection. TMM2 to TMM6 have a much
smaller S1-T1 separation (only about 0.2 eV), and their HOMO and
LUMO levels are more suitable for charge injection.
TABLE-US-00002 TABLE 1 Summary of the energy levels of TMM1 to TMM6
and TEG1 TD-DFT Homo Measured Corr. [eV] Lumo Corr. [eV] T1 [eV] S1
[eV] T1 [eV] TMM1 -5.69 -2.39 2.85 3.28 2.82 TMM2 -5.37 -2.75 2.70
2.94 2.73 TMM3 -5.33 -2.80 2.72 2.95 2.71 TMM4 -5.28 -2.79 2.75
2.96 2.72 TMM5 -5.29 -2.79 2.71 2.92 TMM6 -5.29 -7.28 2.74 2.92
TEG1 -5.33 -2.41 2.68 2.91 2.52
Example 5
Solutions and Compositions Comprising TMM1 to TMM4 and TEG1
[0121] Solutions as summarised in Table 2 are prepared as follows:
firstly, 200 mg of the TMM and 50 mg of TEG1 are dissolved in 10 ml
of chlorobenzene and stirred until the solution is clear. The
solution is filtered using a Millipore Millex LS, hydrophobic PTFE
5.0 .mu.m filter.
TABLE-US-00003 TABLE 2 Composition of the solutions Ratio (based on
Con- Composition weight) Solvent centration Solution 1 TMM1 + TEG1
75%:25% chlorobenzene 25 mg/ml Solution 2 TMM2 + TEG1 75%:25%
chlorobenzene 25 mg/ml Solution 3 TMM3 + TEG1 75%:25% chlorobenzene
25 mg/ml Solution 4 TMM4 + TEG1 75%:25% chlorobenzene 25 mg/ml
[0122] Solutions 1 to 4 are used to coat the emitting layer of
OLEDs. The corresponding solid composition can be obtained by
evaporating the solvent from the solutions. This can be used for
the preparation of further formulations.
Example 6
Production of OLEDs
[0123] OLED1 to OLED4 having a structure in accordance with the
prior art, as depicted in FIG. 1, are produced using the
corresponding solutions, as summarised in Table 2, in accordance
with the following procedure:
1) Coating of 80 nm of PEDOT (Baytron P AI4083) onto an ITO-coated
glass substrate by spin coating. 2) Coating of a 20 nm interlayer
IL1 by spin coating a toluene solution of IL1 (concentration 0.5%
by weight) in a glove box. 3) Heating of the interlayer IL1 at
180.degree. C. for 1 h in a glove box. 4) Coating of an 80 nm
emitting layer by spin coating of a solution in accordance with
Table 2. 5) Heating of the device at 120.degree. C. for 20 min. 6)
Application of a Ba/AI cathode (3 nm+150 nm) by vapour deposition.
7) Encapsulation of the device.
Example 7
Measurements and Comparison of the Results
[0124] The OLEDs obtained in this way are characterised by standard
methods. The following properties are measured: UIL characteristic,
electroluminescence spectrum, colour coordinates, efficiency,
operating voltage and lifetime. The results are summarised in Table
3, where OLED1 serves as comparison in accordance with the prior
art. In Table 3, U.sub.on stands for the use voltage, U(100) stands
for the voltage at 100 cd/m.sup.2 and U(1000) stands for the
voltage at 1000 cd/m.sup.2.
TABLE-US-00004 TABLE 3 Measurement results with OLED1 to OLED4 Max.
eff. CIE @ [cd/A] U.sub.on [V] U(100) [V] U(1000) [V] 100
cd/m.sup.2 OLED1 8.15 3.85 6.60 8.80 0.33/0.62 (comp.) OLED2 31.79
2.64 4.06 5.80 0.34/0.62 OLED3 32.34 2.61 3.99 5.70 0.34/0.62 OLED4
35.12 2.57 3.91 5.65 0.34/0.62
[0125] As can be seen from Table 3, significantly improved
phosphorescent OLEDs with respect to operating voltage and
efficiency are obtained using matrix materials TMM2, TMM3 and TMM4
according to the invention. All OLEDs exhibit comparable colour
coordinates. The high operating voltage and the low efficiency of
OLED1 may be due to the low HOMO and high LUMO of matrix material
TMM1.
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